Pragmatic Unit Testing in Java with JUnit, 3rd Edition

Tests as Documentation

Your unit tests should provide lasting and trustworthy documentation of the capabilities of the classes you build. Tests provide opportunities to explain things that the code itself can’t do as easily. Well-designed tests can supplant a lot of the comments you might otherwise feel compelled to write.

Documenting Your Tests with Consistent Names

The more you combine cases into a single test, the more generic and meaningless the test name becomes. A test named matches doesn’t tell anyone squat about what it demonstrates.

As you move toward more granular tests, each focused on a distinct behavior, you have the opportunity to impart more meaning in each of your test names. Instead of suggesting what context you’re going to ...